Latitudinal biodiversity patterns of meiofauna from sandy littoral beaches

Meiofaunal samples from arctic (Bear Island, Franz Josef Land, Hopen, Kolguev), temperate (Baltic Sea, North Sea) subtropical (Tunisia, Greece), tropical (Emirates, Ghana) and antarctic sandy beaches were collected at the medium water mark. The highest average meiofaunal density was found in the temperate zone (1300 individuals 10 cm(-7)) and the lowest in both polar regions: in arctic (79 individuals 10cm(-2)) and in antarctic (35 individuals 10cm(-2)) samples. Nematodes dominated the meiofauna community in warm regions, while turbellarians were more common in cold water regions. Sixteen higher taxa were recorded in tropical sites, while only eight taxa were observed in the sampled cold regions. This difference was mainly due to the presence of small specimens of macrofauna in the tropics. When only 'true meiofauna' higher taxa were compared, no latitudinal trends were found.